The present invention relates generally to a motion restraint system for a vibratory apparatus such as a vibratory conveyor, and more particularly to an arrangement whereby lateral movement of the vibratory apparatus is restrained while permitting longitudinal and vertical vibratory motion of the apparatus.
Vibratory conveyors and like vibratory apparatus have found widespread use in various types of material-handling applications. These types of devices, typically configured as elongated troughs or trays, are arranged to permit limited longitudinal or longitudinal/vertical motion, such as by mounting of the trough of the apparatus on suspension cables, on elastomeric elements, or by like arrangements. Vibratory motion is induced in the apparatus by mechanical drives (sometimes referred to as exciters), or by electromagnetic drives. Vibratory motion of the apparatus acts to convey material therein, permitting the material to be handled in a gentle fashion, as may be required, and avoiding the complexities of conveyor belts and like arrangements.
Typically, these types of vibratory machines function as feeders or conveyors, and are frequently used to meter the flow of bulk material, or to convey bulk material from one point to another during processing. By way of example, use of these types of vibratory conveyors is widespread in the snack food industry, where they can be advantageously employed to meter products such as potato chips, popcorn, corn chips and the like from storage bins, or to convey and distribute products of this type from cooking processes to packaging machinery.
As will be appreciated, the dynamic forces generated by the operation of such equipment must be isolated from associated support structures, and building structures housing such equipment, to prevent unwanted noise and vibration of the support and building structures, or in the worst case, fatigue and failure of structural components. Isolation systems have been developed to prevent transmission of such forces that are highly efficient, and which are lightly damped in all six degrees of movement (i.e., vertically up and down, longitudinally back and forth, and laterally left and right), thereby allowing the isolated vibratory apparatus to freely move on its isolation system.
Experience has shown that configuring vibratory equipment for movement along all three axes can create problems in those applications where it is necessary to align various pieces of equipment, such as the discharge of one conveyor to the inlet of another. This can be particularly troublesome in those applications where the isolation system for the apparatus uses long suspension cables to achieve the desired application, such as in a single mass machine with a differential motion conveyor. While the differential motion conveyor has virtually no vertical component of vibration (hence the length of the cables to ensure this), it has a relatively large horizontal motion which, coupled with the length of the suspension cables, can undesirably result in erratic, high amplitude swinging of the conveyor, if any unbalanced, off-axis forces are present. Such forces are difficult to eliminate entirely because even geometric manufacturing tolerances over a long conveyor can create a dynamic, unbalanced force sufficient to initiate a swinging motion in the conveyor.
Lateral swinging motion of a conveyor can particularly complicate maintaining the conveyor""s alignment, and undesirably result in product spills at transition points, contributing to product loss, as well as sanitation and clean-up expenses. While it is known to limit lateral motion of a conveyor, such as by providing stationary tracks upon which a suspended conveyor rides, such systems are not only costly to install and maintain, they do not always constrain the unwanted motion, can be noisy and difficult to clean, and can add considerably to the cost of installation for the conveyor arrangement.
The present invention contemplates an arrangement for restraining lateral movement of a vibratory apparatus, such as a vibratory conveyor, which comprises a desirably straightforward and relatively low cost design. The present system is easy to install, straightforward to maintain and clean, is of a sanitary construction, and is quiet in operation. While the present disclosure illustrates the present motion restraint system in connection with a vibratory conveyor apparatus, it will be understood by those skilled in the art that the present system may find application in connection with controlling motion of other vibratory devices.
The motion restraint system of the present invention includes a pair of spaced apart support structures which are positioned in operative association with a vibratory apparatus such as a vibratory conveyor. In accordance with an illustrated embodiment of the invention, the spaced apart support structures comprise a pair of A-frame pedestals from which the vibratory conveyor apparatus is suspended. The support structures are fixedly mounted and anchored to the associated floor or like structure within which the vibratory apparatus is housed.
The present motion restraint system further includes a flexible restraint member which extends between and is connected to the spaced apart support structures. In the preferred form, the flexible restraint member comprises a wire rope which is positioned beneath the vibratory conveyor apparatus with opposite ends of the wire rope connected to the associated support structure. While the flexible restraint member is fitted to the associated support structures with sufficient tension so as to limit the range of flexible movement of the member, the member exhibits sufficient flexibility as to accommodate the normal vibratory movement of the associated apparatus, such as in the generally longitudinal direction thereof.
A connection element mounted on the vibratory apparatus is connected to the flexible restraint member intermediate the laterally spaced apart support structures. By this arrangement, the present system acts to restrain lateral movement of the vibratory apparatus while permitting movement thereof along the generally longitudinal direction. As will be recognized by those familiar with the art, some vibratory devices not only exhibit generally longitudinal movement, but vertical movement as well, and the configuration of the present restraint system, including a flexible restraint member connected to the vibratory apparatus, accommodates longitudinal and vertical vibratory motion, while acting to limit and restrain lateral motion of the apparatus.
The present system preferably includes a pair of isolation elements which are operatively interposed between the restraint member and the respective ones of the spaced apart support structures to isolate the support structures from the movement of the flexible restraint member. In the illustrated embodiment, the isolation elements comprise elastomeric elements respectively mounted on the support structures. Each elastomeric isolation element defines an internal passage through which the flexible restraint member extends. In this fashion, movement of the restraint member attendant to vibratory movement of the associated apparatus results in engagement of the restraint member with the isolation elements, thus cushioning the horizontal and vertical motions of the restraint member, abating or eliminating noise caused by the vibration, and desirably acting to prevent fatigue failure of the wire rope from which the restraint member is formed.
Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claims.